Electric elevator-control system



Dec. 28 1926.

1,612,302 r E. s. MATTHEWS ELECTRIC ELEVATOR CONTROL SYSTEM Filed March 12. 1923 f I v/J3 J/ 49 1 JUL..

1 fily 10 "-32 h \i J/ INVENTOR Patented Dec. 28, 1926.

UNITED STATES PATENT OFFICE;

ELECTRIC ELEVATOR-CONTROL SYSTEM.

Application filed March 12, 1923. Serial No. 624,899.

The object of this invention is the provision of means to assist persons operating elevators to stopthe car within prescribed limits of close proximity to the various landings which it serves.

It is particularl useful in passenger elevators but its use 1s not restricted thereto.

Frequently in busy passenger elevators the car is so crowded with passengers as to prevent an operator from properly seeing the landing as he approaches it, thus preventing the most skillful and conscientious operator from shutting off the powerat the right time to properly-stop the car.

In the case of'electric elevators, suitable control of the speed of the car while running under power, and just before it is brought to rest with a diminishing sliding motion due to brake retardation causes the ensuing stop to be made with a good degree of ac curacy.

Hence this invention 1s particularly adapted to be used in connection with the speed control of an elevator whose motor is operated in the manner set forth in my United States Patent No. 1,490,673issued April 15, 19:24, Where all the details of a system of control for elevator motors are set forth.

However, its use is not restricted to that controlling mechanisms are in common use for terminal landings; but this invention, provides the operator with a supplementary. manually cont-rolled stop acting in either direction of travel for any or intermediate landings which he. can use or not as he chooses and in the way he chooses, and which does not supersede the usual control which latter is usable by the operator To stop the car of an electric elevator exactly at a given point it is necessary to shut oli' the motive power at exactly the right point in its travel, from which point the car slides onward under retardation of the brake and other forces until it comes to rest, as is Well known.

Automatic. landing stops for electric elevators heretofore in use have shut oil the power arbitrarily as a result of car motion, at some given point determined by car lo; cation, in the travel of the elevator.

Now the retarding forces in effect during the sliding stop of an electric elevator are variable, and particular-l the frictional resistance of the brake,"ca les, etc., varies according to-the condition-and state of adjustment of the apparatus, and the extent to which it is limbered up.

The method of operating a landing stop for electric elevators, by causing the motion of the car to effect the shutting off of the power at a variable point in the travel of the elevator according to the amount of sliding the elevator will subsequently do in coming to a stop now set forth in this specification, is broadly new, as far as the applicant is aware.

In this embodiment of that feature of this invention the operator varies the above mentioned point according to his observation and knowledge of the sliding conditions of the elevator car at the time the stop is to be made; and, since by the use of this invention, he does not need to see his landing in order to find it or make it properly, (as will become manifest) he is enabled to closely watch sliding conditions and rightly allow for them.

Other features and objects of this invention will become manifest to those skilled in the art as its typical embodying instrumentalities and its operation are later explained, and its novel features are pointed out in the claims.

The exemplifying structure herein shown is illustrated by a dia rammaticdrawing, usual conventionalities being en'iployed, and this structure and its oeration will now be described in detail, re 'erence being bad to the drawing, in which i Fig. 1 shows an elevator machine with a controller, connected thereto located above an elevator car which is suspended from the if desired in an alternative indirect manner by a sparldess relay shown in the upper left portion of this figure, through wiring connections, shown at the left of the conducting lates.

Fig. 2 shows a transverse section of the opcrating switches on the side ofthe car, and of the hatchway and typical ccntactplates of one of the landings in their relative positions when the car is level with the landing as shown in Fig. 1,v I

Fig. 3 is an enlarged drawing of the typical landingcontact plates.

Current supply enters the apparatus. at the signs and at the right hand side of the drawing. 1

10 represents an elevator car and 11 a pivoted lever or car switch for manually controlling the apparatus mounted upon an insulating control board or upon the side of the car itself if formed of insulating material as vshown, which has a slot'13 of definite len th cut through it which extends through the side wall of the car at that point;

This slot is preferably cur ed on a radius" from the pivot point 14: of the car switch lever and of a width sutlicient to permit the push button stem 1 5 carrying current to pass freely through it, and of a length suificient to permit a considerable swing of the car switch while the push button stem is protruding through the slot, but not long enough to permit the car switch, at such times to make connection with either carrunning contact 16 or. 17 which are respectively the upand down motion contacts for operating the car with the speed in use just before the'supply to the motor armature is severed for making the necessary sliding stop which brings the car to rest. a

This car. switch may also have highe speed contacts more remote from the center than 16 and 17 but as they are not material to this invention they are notherein described. 1 y

18 represents the electric hoisting,- lowering and sustaining machine (of the traction type) by which the elevator is operated; having a traction sheave, motorfriction brake and other appurtenances and well known in such machines.

'19 represents a cable or cables sustaining the car and counterweight 20, being attached thereto and governed in positioh by their contact with the traction sheave of 18; 7

parts I amazon through conduit 22.

23 and 26' represent two intermediate landings served by'the elevator car, although the constructions and mode of operation herein shown is applicable to terminal landings; in which case the full automatic terminal stop of the apparatus is arranged to occur at a point a little beyond such terminal landing; and is used as an emergency stop only. I

24 and 25 represent two insulated conducting close to t e car as it moves by them, and in a plane parallel to that motion and to the swing of lever 11; being located so that when push button stem 15 is pushed outwardly by the operator it will make contact with these plates when opposite -to them. They are ocated with an aperture betweenthem arran 'ed so that when the car is as near the lan ing as may be required and the lever 11 is in central position with the stem 15 pushed toward. the plates as far as possible it will will be made with plate 24 and if too low 'Irom the landing contact will be made with plate 25.

27 and 28 are corresponding conducting plates for landing 26, and all landings where it is desired to operate this apparatus are provided with similar plates, similarly arranged with reference to the landing and their electric connections are also similar.

The aperture between these contacting plates is greater at their side edges than at their center (see plates 27 and 28) and is so arranged that the maximum vertical length of possible contact of push button 15 with either plate gradually diminishes as it is swung from center positionin either direction, the extent of this motion being limited by slot 13; as is shown by dotted line 29 :eprpgenting the arc of motion of push butthis are of motion so located that whenthe pushed in push button stem reaches it, in course of the motion of car toward the landing, the o erator can feel the groove (although it oes not affect the electric circuit) and thus learn that the car has approachednearlyto the landing whether he can see the landing or not. i

lates attached to the 'hatchway, 1

Hill

In each of these plates a groove is cut on I This push button stem 15 moves longitudinally through a hole in the center of the operating handle and is held normally pushed back from contact-with the conducting plates 24, 25-, 27, 28 etc, by the spring 40; so that the force necessary to make such a contact is supplied by the operator, and in this embodiment of the invention he must continually force 15 against the plate while floor finding by means of this apparatusis in progress, hence he readily feels the passage of 15 over the grooves 39, although these grooves may be omitted if desired, as they are not a necessity to. the operator and floor finding is accomplished satisfactorily without them.

vOther means may be used to apprise the operator of the location of the car relative to an unseen landing, and the electric circuits and means herein shown may be modified for the use of an operator who is not located in the elevator car without departing from the spirit of this invention.

As herein illustrated the lowest speed of the ordinary car switch control is used in floor finding, and when this speed is dependable for such purpose as in the system of motor control shown in U. S. Patent- No. 1,490,673, issued April 15, 1924, this is a preferredarrangement; but in the case of some existing motor control systems the lowest car switch speed cannot be depended upon for fioor finding work.

In such cases the conducting plates are wired byseparate individual leads, not connected with the car switch leads, to the starting, reversing and stopping switch of the slow speed floor finding power apparatus which may be provided from the Ward Leonard System, a multi-voltage system, dynamotor system, or auxiliary. motor system; the only necessity being that such power apparatus shall fulfill the rudimentary requirements of dependability, reversibility, of being brought into action and of being stopped by an electric switch, and of holding the load when stop ed.

The operation of the erein described apparatus will now be ex lained and in that connection the electric clrcuits which are of a simple character will be described in detail.

Two sets of electric circuits are shown, one for direct operation shown at the right of the conducting plates and the other for induction neutrahzin r sparkless relay operation shown at the left of the conducting plates, either one of which systems may be used.

As shown in the drawing the car is at the landing 23 and no circuit is in use in the direct operation system and only the holding circuit of the relay system if that system is in use, instead of the other.

The direct operating system will be first described after which the relay system will be readily understood.

In case the elevator is operated to go from landin 23 to landing 26 and the latter is made y the floor finding system, no atten- .Ina gnetic reversing and current supply switch of the elevator motor'being properly operated by the current from through wire 30 contact. 17, wire 34 and wire 32 leading to the down motion switch coil, thence through wire 41 to the main. Motor supply is from throughwire 2S), conduit 22, the motor, conduit 22 and wire 41 to the main.

As the car approaches landing 26 the v operator moves his switch 11 toward central position releasing contact 17 presses in push button stem 15 making contact with plate 27 which causes the elevator to. run onits downward slow adjusting speed as long as he continues his pressure of 15 until by the continued motion of the car, contact 15 runs off plate 27 cutting off the power and stopping the car. If he keeps his car lever in exactly central position this con: tact will be maintained and the circuit through wire 32 continued until the car stops exceedingly close to the landing 26 if not exactly at it, with a light load in the car, and prompt'and eflicient brake action.

If, however, the car is heavily-loaded and the brake is in inefiicient condition causing an excess of slip in stopping the car, the operator upon pressing 15 will keep his lever as far from the center as the construction permits thus causing the push button con tact 15 to run ofi the plate 27 as soon as possible, consequently cutting off power and applying the brake at the earliest moment the nature of the floor finding apparatus will permit.

The result isthat the car stops near or at the landing. If the stop is satisfactory he releases the push button.

If he brings his lever to'the center while maintainin his pressure on the push button, there will be no result if the car is exceedingly close to the landing.

If not, the push button 15 will again make contact with a conducting plate, and the farther the car is away from proper position the more quickly such a contact will be made. I

If in this manipulation of the apparatus the car is below thelanding but not suiiiciently so to bring the pushed button in contact with upward car moving conducting plate 28 while the lever 11 is remote from its central position, the bringing it to or towards center position will cause pushed button 15 to make contact with plate 28 and the car to move upwardly at slow speed toward the landing and since upward car movement causes 15 to run off of plate 28 e the car in such case is brought by the operplate 27, wire 38, wire 32 leading to the.

proper down motion reversing switch coil thence through wire 41 to the main.

The circuit for the upward car moving conducting plate 28 is from the main wire 30, lever 11, pushed button 15, plate 28, wire 37, wire 31 to the proper up motion reversing switch coil, thence through wire 41 to the main.

All upward and downward car moving conducting plates including 24 and are connected in a similar manner.

The circuits for induction neutralizing sparkless relay operation'of this apparatus are shown with the coils and switches for the same at the left of the elevator car in the drawings.

When this apparatus is used in place of the direct operation heretofore described. the switch having contacts 42 and 43 brings into action the upward moving slow floor finding speed of the apparatus, through the same switches as the direct operation uses, whenevcr these contacts are closed by gravity action ;or stops its operation when they are separated by'magnetic action as shown in the drawings; and switch with contacts 44 and 45 similarly controls the downward moving slow floorfinding speed. Contacts 42 and 44 are both connected to the supply from wire 49 through wire 46. Coils 47 and 48 are in constant circuit from supply through wires 49 and 50 and to the main 41 by wires 51, 52 and 53 and their magnetic excitation holds their respective switches open as shown in the drawing, since coils 54 and 55 are not excited in the position of elevator apparatus shown 1n the drawings. Coils 54 and 55 :rre of opposite polarity to coils 47 and 48 with which they are respectively associated and when-47 is excited the double coil 47, 54 loses'all mag netism. and double coil 48, 55 operates in the same manner, Hence, whcncoil 55 is excited contact 45 falls into contact with 44, and when 54 is excited contact between 43 and 42 is made in a similar manner.

Coil 55 is connected to all downward car moving conducting plates by wires 56 which connects to plate 24 from which wires lead to all similar plates as is now understood from which electricity is received by this coil whenever pushed button 15 contacts with any such plate as heretofore described, and

the circuit is completed through wires 57 and 53 to the main 41.

Coil 54 is similarly connected to all downward car moving conducting plates being connected to plate 25 through Wire 58, and to main through wire 53.

It is now obviousthat these switches act as relays in accomplishing the results of the directeonnections from all conducting plates, and that there can be no inductive sparking when pushed button 15 leaves any conducting plate from any circuit through either relay double coil 47, 54 or 48, 55.

The actuating electro-magnets for the slow power reversing switches, operated by the direct operation system, are preferably constructed in the same manner asthese heretefore described for the relay system operation; thus avoiding sparking at actuating contacts in the use of that system.

In such: case the regular reversing switch multiple contacts with their proper leads to the motor are substituted for the single contacts 42 to 43 and 44 to 45.

Many variations in the construction and details and location and arrangement of parts would readily suggest themselves to those skilled in the art to which this invention relates and still fall within the spirit and scope of my invention; hence I do not desire to be limited to the exact construction herein set forth; but having explained the principles of my invention and a preferred form of apparatus embodying it, and

Having described the function, purpose, and mode of operation of such apparatus what I claim is new and of my own invention, and desire to secure by Letters Patent of the United States is,

1; In an electric elevator the combination ii of the car, a hoisting, lowering, starting, stopping and sustaining electric motor machine, electric means to control the operation of said machine, with additional means constructed and arranged to be operable manually at all tunes when the car 1s 1n the.

region of a landing, but not at it, to stop or start said maclnne; and further control- .lable, as to direction of car motion which may be 1mparted from sald machine, by the,

position of the car with reference to the landing, whep in its region but not at the 1 landing, and" also controllable to stop the car at the landing only by the action of the operator or the joint action of the operator and the movement of the car.

2. In an electric elevator the combination of the car, an electric hoisting motor, electricmeans to control the motor, controllable unitedly by the position of the car, and a operation of the motor to approximate to and later stop at said landing from either direction, which stopincapacitates said switch from action while the car remains at said landing.

3. In an elevator the combination of a car, a motor having a running speed and a slower adjusting speed, a car switch for controlling the running and adjusting speed operation of the motor, and a supplementary car switch for bringing into action or cutting out of action the adjusting speed of the motor, only after the first-named car swit::h

- has'relinquished its control of the motor.

4:. In an elevator the combination of a car, a motor having a running speed and a slower adjusting speed, a car switch forcontrolling the running and adjusting speed operation of the motor, a supplementary car switch for bringing into action or cutting out of action the adjusting speed of the motor, only after the first-named car switch has relinquished its control of the motor, and a contact for said switch determining the direction of motor rotation according to the position of the car in the hatchway.

5,. In an elevator the combination of a car, a motor having a running speed and a slower adjusting speed, a car switch for controlling the running and adjusting speed operation of the motor, a supplementary car switch for bringing into action or cutting out of action apparatus therefor, including means oper-.

ating to stop the car near some fixed point in its extent of travel as a result of its own motion, with means controllable by the operator constructed and arranged for manually varying the proximity to said fixed point at which such stopping means operates.

7. In anelectric elevator the combination of the car, an electrically operated motor therefor, electric means to control the motor, including means for controlling an' electric circuit by making or breaking the same so as to stop the motor as a result of the motion of the car when the latter is near some fixed point in its extent of travel with means a controllable by the operator constructed and arranged for manually varying the proximit to said fixed point at which the brea 'ng of said circuit occurs.

8. In an elevator, the combination of the car, motive and controlling means for raising, lowering, starting, stopping and sustaining the car, with an operator controlled switch effective for starting, stopping or continuing the motion of the car only when it is in the region of a given fixed point in its travel but ineffective to cause any car motion when the car is substantially at said fixed point.

9. In an elevator, the combination of the car, motive and controlling means for raising, lowering, starting, stopping and sustaining the car, with an operator controlled switch effective for starting, stopping, or continuing the motion of the car only when it is in the region ofa given fixed point in its travel and causing it to move toward said given fixed point only.

10. In an elevator, the combination with the carof means constructed and arranged to give the operator opportunity to become aware of the proximity of an approaching car to its coming landing, independently of visual observation, said means being operative only in the off position of the controller member.

11. In an elevator, the combination of the car, motive and controlling means for rais-- ing, lowering, starting, stopping and sustaining the car, with an operator controlled switch effective for starting, stopping or continuing the motion of the car only when it is in the region of a given fixed point in its travel, and causing it to move toward said given fixed point only, but ineffective to cause any car motion when the car is a substantially at said given fixed point.

v12. In an elevator, the combinatit not the car, motive, sustaining and controlling means therefor, with two manually operable controlling switches which are operable separately but not unitedly; one of which is effective to stop or start the car in any.

position which it may occupy in its extent of travel, while the other is operative only to cause the car to approach a neighboring landing, and to stop the car wherever desired in such approach, but having no control over car motion when the car is substantially at the landing.

13. In an elevator, the combination of the car, motive and sustaining apparatus, controlling means therefor comprising an electro-magnetically operated switch for starting, stopping or continuing the motion of saidcar, the actuating coil of said switch being provided with a circuit constructed, arranged and connected so as to be governed by the osition of the car in the hatchway as to the possibility of said circuit being made or broken, and means to prevent arc ing when said circuit is broken.

14. In an elevator, the combination of the car, motive and sustaining apparatus, controlling means therefor comprising .an election of the car in the hatchway as to the tro-magnetically 0 erated switch for start,- possibility of said circuit being made or 10 ing or continui'zg t e motion of the car only broken, and means to prevent arcing when to cause the car to approach a neighboring said circuit is broken.

a landing, or for stopping said car, the actu- In testimony whereof, I have signed my ation coil of said switch being provided name to this specification.

with a circuit constructed, arranged and connected so as to be governed by the posi- EDWIN S. MATTHEWS. 

